ANALYSIS OF ENVIRONMENTAL AIR SAMPLES BY SOLID-PHASE MICROEXTRACTION AND GAS-CHROMATOGRAPHY ION-TRAP MASS-SPECTROMETRY

A simple and efficient method for extraction and concentration of vola tile organic compounds (VOCs) in air using solid-phase microextraction (SPME) has been developed. The analytes are extracted directly from t he air and desorbed into a gas chromatograph for separation and quanti fication. This method requires minimal sample preparation time and, th erefore, is suitable for on-site air monitoring. Analytes can be detec ted at the part per trillion (ppt) to sub part per billion (ppb) conce ntration levels with an ion trap mass spectrometer. The precision of t he method was determined to be 1.5-6% relative standard deviation (RSD ). Temperature and humidity effects were studied experimentally, and t he method was compared with an EPA-validated method for selected VOCs. The SPME technique may be suitable for both spot sampling and integra l exposure over time sampling. Integrated sampling has been successful ly applied to the identification and quantification of toxic volatile organic compounds in environmental air samples.